| RefNo | Title | Date |
| EC/1895/12 | Holden, Sir Henry Capel Lofft: certificate of election to the Royal Society | |
| IM/Maull/002175 | Holden, Sir Henry Capel Lofft | nd |
| NLB/13/549 | Copy letter from Robert William Frederick Harrison, to Messrs Harrison & Sons | 6 October 1896 |
| NLB/30/851 | Copy letter from Robert William Frederick Harrison, to Lieutenant Colonel Henry Capel Lofft Holden, Fellow of the Royal Society | 31 May 1905 |
| NLB/32/542 | Copy letter from Joseph Larmor, to Colonel [Henry Capel Lofft] Holden, [Fellow of the Royal Society] | 29 March 1906 |
| NLB/33/728 | Copy letter from Robert William Frederick Harrison, to Lieutenant-Colonel Henry Capel Lofft Holden, Fellow of the Royal Society | 26 October 1906 |
| NLB/38/392 | Copy letter from Robert William Frederick Harrison, to Colonel Henry Capel Lofft Holden, Fellow of the Royal Society | 28 July 1908 |
| NLB/35/319 | Copy letter from Robert William Frederick Harrison, to Colonel Henry Capel Lofft Holden, Fellow of the Royal Society | 15 May 1907 |
| NLB/36/408 | Copy letter from Robert William Frederick Harrison, to Colonel Henry Capel Lofft Holden, Fellow of the Royal Society | 26 October 1907 |
| NLB/36/752 | Copy letter from Robert William Frederick Harrison, to Lieutenant Colonel Holden, Fellow of the Royal Society | 11 December 1907 |
| NLB/52/537 | Copy letter from Robert William Frederick Harrison, Assistant Secretary of the Royal Society; to Messrs Harrison & Sons | 10 January 1916 |
| ACS/1/2/2/223 | Letter from [Alan Archibald Campbell] Swinton, to [Brigadier] Sir [Henry Capel Lofft] Holden, K. C. B, F. R. S. | 15 March 1927 |
| NLB/3/272 | Copy letter from Herbert Rix, to Professor Alfred George Greenhill, Fellow of the Royal Society, 3 Staples Inn, W.C. | 26 April 1889 |
| RSC/5/9/10 | Letter from S F [Sidney Frederic] Harmer, 30 Courtfield Gardens, to [Henry Capel Lofft] Holden | 22 February 1923 |
| AP/77/4 | Unpublished paper, 'Constants of explosion of cordite and of modified cordite' by Robert Robertson | 21 March 1905 |
| AP/77/4/1 | Unpublished manuscript, 'Constants of explosion of cordite and of modified cordite' by Robert Robertson | 21 March 1905 |
| RSC/5/9/2 | Letter from Alexander Scott, 34 Upper Hamilton Terrace, to [Henry Capel Lofft] Holden | 1 July 1922 |
| RSC/5/9/12 | Letter from W W [William Whitehead] Watts, Hillside, Langley Park, Sutton, Surrey, to Sir [Henry] Capel [Lofft Holden], 30 Courtfield Gardens | 25 February 1923 |
| MS/928/2/96 | Letter from Henry Capel Lofft Holden, Royal Arsenal, to Charles Vernon Boys | 21 November 1892 |
| MC/22/123 | Letter from Henry Capel Lofft Holden, Gifford House, St John's Park, Blackheath, to [Robert William Frederick] Harrison | 27 October 1907 |
| ACS/1/2/2/209 | Letter from [Alan Archibald Campbell] Swinton, to Brig-General., Sir [Henry Capel Lofft] Holden, K. C. B., F.R. S. | 11 March 1927 |
| RSC/5/9/18 | Letter from S F [Sidney Frederic] Harmer, 30 Courtfield Gardens, to [Henry Capel Lofft] Holden | 27 April 1923 |
| RSC/5/7/28 | Letter from S F [Sidney Frederic] Harmer, 30 Courtfield Gardens, to [Henry Capel Lofft] Holden | 25 March 1923 |
| RSC/5/9/15 | Letter from S F [Sidney Frederic] Harmer, 30 Courtfield Gardens, to [Henry Capel Lofft] Holden | 15 March 1923 |
| RSC/5/9/3 | Letter from S F [Sidney Frederic] Harmer, 30 Courtfield Gardens, to [Henry Capel Lofft] Holden | 11 December 1922 |
| RSC/5/9/7 | Letter from W H [William Henry] Bragg, University of London, University College, Gower Street, to [Henry Capel Lofft] Holden | 2 December 1922 |
| RSC/5/9/19 | Letter from W H [William Henry] Bragg, University of London, University College, Gower Street, to Brig. General Sir [Henry] Capel [Lofft] Holden, Gifford House, St. John's Park, Blackheath | 27 April 1923 |
| RSC/5/9/20 | Letter from W H [William Henry] Bragg, University of London, University College, Gower Street, to [Henry Capel Lofft] Holden | 11 May 1923 |
| RSC/5/9/21 | Letter from W H [William Henry] Bragg, University of London, University College, Gower Street, to [Henry Capel Lofft] Holden | 17 November 1923 |
| RSC/5/9/14 | Letter from Alexander Scott, 34 Upper Hamilton Terrace, to [Henry Capel Lofft] Holden | 12 March 1923 |
| RSC/5/7/25 | Letter from W W [William Whitehead] Watts, Hillside, Langley Park, Sutton, Surrey, to Sir Capel [Holden] | 6 March 1923 |
| RSC/5/7/26 | Letter from W W [William Whitehead] Watts, Hillside, Langley Park, Sutton, Surrey, to Sir Capel [Holden] | 13 March 1923 |
| RSC/5/7/30 | Letter from W W [William Whitehead] Watts, Hillside, Langley Park, Sutton, Surrey, to Sir Capel [Holden] | 3 April 1923 |
| RSC/5/7/31 | Copy letter from H C L [Henry Capel Lofft] Holden, Gifford House, St John's Park, Blackheath, to [Macmillan & Company] | 6 April 1923 |
| RSC/5/7/27 | Letter from H C L [Henry Capel Lofft] Holden, 2 St John's Park, Blackheath, to [Sidney Frederic] Harmer | 20 March 1923 |
| RSC/5/9/8 | Letter from C F [Constance Fligg] Elam, 7 Little St Mary's Lane, Cambridge, to the Treasurer of the Royal Society Club [Henry Capel Lofft Holden] | 21 February 1923 |
| RSC/5/9/13 | Letter from S F [Sidney Frederic] Harmer, 30 Courtfield Gardens, to [Henry Capel Lofft] Holden | 28 February 1923 |
| RSC/5/9/16 | Letter from Constance F [Fligg] Elam, 7 Little St Mary's Lane, Cambridge, Sir Henry [Capel Lofft] Holden, 1 Temple Gardens [redirected from Jukes Hotel, 8 Jermyn Street] | 23 March 1923 |
| RSC/5/9/17 | Letter from Constance F [Fligg] Elam, Royal School of Mines, Imperial College of Science and Technology, South Kensington, London, to Sir Henry [Capel Lofft] Holden, 1 Temple Gardens [redirected from Jukes Hotel, 8 Jermyn Street] | 7 May 1923 |
| RSC/5/9/4 | Letter from N I Blair [?], John Haig & Co., Limited, 79 Mark Lane, London, to Brig. Gen. Sir [Henry] Capel [Lofft] Holden, Senior Treasurer, Royal Society Club, Gifford House, St John's Park, Blackheath | 18 December 1922 |
| RSC/5/9/5 | Letter from Eric Fald, St James's Advertising and Publishing Company, 1 Wardour Sttreet, London, to Brig. Genl. Sir [Henry] Capel [Lofft] Holden, Gifford House, St John's Park, Blackheath | 22 December 1922 |
| RSC/5/9/1 | Letter from Alexander Scott, 34 Upper Hamilton Terrace, to [Henry Capel Lofft] Holden | 27 June 1922 |
| RSC/5/9/11 | Minutes of a meeting of the Royal Society Club, compiled by S F [Sidney Frederic] Harmer, 30 Courtfield Gardens | 22 February 1923 |
| MC/22 | Volume 22 of miscellaneous correspondence regarding business matters, sent to the Royal Society | 1907 |